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Message-ID: <f83adfd4df5cd23176721087a4fcd9a0225c3483.camel@gmail.com>
Subject: Re: [PATCH v4] Fix IRQ issue by setting IRQ_DISABLE_UNLAZY flag
From:   Nuno =?ISO-8859-1?Q?S=E1?= <noname.nuno@gmail.com>
To:     Masahiro Honda <honda@mechatrax.com>,
        Lars-Peter Clausen <lars@metafoo.de>,
        Michael Hennerich <Michael.Hennerich@analog.com>,
        Jonathan Cameron <jic23@kernel.org>
Cc:     linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org
Date:   Wed, 03 May 2023 10:09:28 +0200
In-Reply-To: <20230502102930.773-1-honda@mechatrax.com>
References: <20230502102930.773-1-honda@mechatrax.com>
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On Tue, 2023-05-02 at 19:29 +0900, Masahiro Honda wrote:
> The Sigma-Delta ADCs supported by this driver can use SDO as an interrupt
> line to indicate the completion of a conversion. However, some devices
> cannot properly detect the completion of a conversion by an interrupt.
> This is for the reason mentioned in the following commit.
>=20
> commit e9849777d0e2 ("genirq: Add flag to force mask in
> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 disable_irq[_nosync]=
()")
>=20
> A read operation is performed by an extra interrupt before the completion
> of a conversion. This patch fixes the issue by setting IRQ_DISABLE_UNLAZY
> flag.
>=20
> Signed-off-by: Masahiro Honda <honda@mechatrax.com>
> ---

Reviewed-by: Nuno S=C3=A1 <nuno.sa@analog.com>

> v4:
> =C2=A0- Remove the callback.
> v3:
> https://lore.kernel.org/linux-iio/20230420102316.757-1-honda@mechatrax.co=
m/
> =C2=A0- Remove the Kconfig option.
> v2:
> https://lore.kernel.org/linux-iio/20230414102744.150-1-honda@mechatrax.co=
m/
> =C2=A0- Rework commit message.
> =C2=A0- Add a new entry in the Kconfig.
> =C2=A0- Call irq_clear_status_flags(irq, IRQ_DISABLE_UNLAZY) when freeing=
 the IRQ.
> v1:
> https://lore.kernel.org/linux-iio/20230306044737.862-1-honda@mechatrax.co=
m/
>=20
> =C2=A0drivers/iio/adc/ad_sigma_delta.c | 4 ++++
> =C2=A01 file changed, 4 insertions(+)
>=20
> diff --git a/drivers/iio/adc/ad_sigma_delta.c
> b/drivers/iio/adc/ad_sigma_delta.c
> index d8570f6207..7e21928707 100644
> --- a/drivers/iio/adc/ad_sigma_delta.c
> +++ b/drivers/iio/adc/ad_sigma_delta.c
> @@ -584,6 +584,10 @@ static int devm_ad_sd_probe_trigger(struct device *d=
ev,
> struct iio_dev *indio_de
> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0init_completion(&sigma_de=
lta->completion);
> =C2=A0
> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0sigma_delta->irq_dis =3D =
true;
> +
> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0/* the IRQ core clears IRQ_DIS=
ABLE_UNLAZY flag when freeing an IRQ */
> +=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0irq_set_status_flags(sigma_del=
ta->spi->irq, IRQ_DISABLE_UNLAZY);
> +
> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0ret =3D devm_request_irq(=
dev, sigma_delta->spi->irq,
> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 ad_sd_data_rdy_trig_poll,
> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 sigma_delta->info->irq_flags | IRQF_NO_AU=
TOEN,